Begin by switching off the cell phone by holding the Power key for a while.Afterwards press and hold together: Volume Up + Home + Power button for a couple of seconds.You should release held keys as soon as the Samsung Logo appears on the screen.Then select "wipe data / factory reset" using Volume buttons to navigate and Power button to confirm.Choose "Yes -- delete all user data" to confirm the whole operation.In the next step select option "reboot system now".Well done! You have just performed the hard reset operation.

OR

Start by turninng on the device by holding down the Power key for a few seconds.From the Home Screen go to Menu and then to Settings.Afterwards tap Backup & Reset and then Factory data reset.In the next step choose Reset phone.To confirm your choice select Erase everything.That's all. The hard reset is done.